The present invention is intended to be an improvement on a sanding tool previously patented by myself and Arlen Ingram in U.S. Pat. No. 4,694,618 dated Sept. 22, 1987. The Ingram device utilized a metal frame with a handle at one end and spaced parallel bars connected by a slightly resilient rod. A closed loop of abrasive material is suspended between the bars and tensioned by the connecting rod.
Other patents include Miller U.S. Pat. No. 2,424,702 (1947) on an abrasive strip holder, and Bonapace U.S. Pat No. 3,871,141 (1975) on a knife sharpener. Miller shows a tapered belt looped over at one end on a solid mandrel and carried at the other end on a lateral peg on a handle body element. Bonapace shows a knife sharpener with a tensioning head backed by a coil spring.
The present invention has as an object the provision of a sanding tool with three elemental parts using a flat closed loop which can be tensioned by a threaded adjustment and which is so designed that it can be inserted to narrow crevices with no interference from the supporting frame. The supporting structure provides a double faced sanding tool which increases from a vary narrow distal end to a wide proximal end so it can be utilized on one or both sides in closely spaced parts.
In brief, the object of the invention is achieved by three main parts. A first basic body part has at a distal end a narrow reaction cross-bar extending transversely of the axis of the body. The body has an elongate torque which tapers from a narrow dimension at the cross bar to a wider square or rectangular head end. Beyond the head end is a control shaft also on the axis of the body. A second element is a proximal sanding loop retainer having an opening to receive the control shaft and also a square or rectangular opening to receive the head end of the body. The second element has also a threaded extension boss element, internal or external, opposite the square opening to receive the third element. The third element is a hollow handle and tension control device which receives the control shaft and has also a threaded element to cooperate with the threaded boss of the second element.
An abrasive band is formed as a loop with an aperture to receive the threaded boss as the parts are assembled. In assembly, the boss of the second element is located in the aperture at one end of the abrasive loop, the basic body is positioned with the cross bar at the other end of the loop and the control shaft is passed through the second element into the hollow handle. The threaded elements are engaged and the handle is screwed onto the retainer. This will tension the sanding loop. The limit of the tension can be controlled by the shaft abutting the end of the hollow passage.
Additional objects and features of the invention will be apparent in the following description and claims in which the principles of the invention are set forth together with details to enable persons skilled in the art to practice the invention, all in connection with the best mode presently contemplated for the invention.